scholarly journals Evaluation of the friction force generated by monocristalyne and policristalyne ceramic brackets in sliding mechanics

2013 ◽  
Vol 18 (1) ◽  
pp. 121-127 ◽  
Author(s):  
Roberta Ferreira Pimentel ◽  
Roberto Sotto Maior Fortes de Oliveira ◽  
Maria das Graças Afonso Miranda Chaves ◽  
Carlos Nelson Elias ◽  
Marco Abdo Gravina
Keyword(s):  
Friction Force ◽  
Artificial Saliva ◽  
Testing Machine ◽  
Friction Coefficients ◽  
Friction Forces ◽  
Maximum Friction ◽  
Steel Wires ◽  
Ceramic Brackets ◽  
Sliding Mechanics

OBJECTIVE: To evaluate and compare "in vitro" the maximum friction force generated by three types of esthetic brackets, two types of polycrystalline conventional ceramic brackets (20/40 and InVu) and one type of sapphire monocrystalline bracket (Radiance) in dry and artificial saliva wet settings. Also, to evaluate the influence exerted by artificial saliva on the friction forces of those brackets. METHODS: Tests were performed in dry and artificial saliva wet setting (Oral Balance) by using an EMIC DL 10000 testing machine, simulating a 2 mm slide of 0.019 x 0.025-in rectangular stainless steel wires over the pre-angulated and pre-torqued (right superior canine, Roth prescription, slot 0.022 x 0.030-in) brackets (n = 18 for each bracket). In order to compare groups in dry and wet settings, the ANOVA was used. For comparisons related to the dry versus wet setting, the student t test was used for each group. RESULTS: The results showed that in the absence of saliva the Radiance monocrystalline brackets showed the highest friction coefficients, followed by the 20/40 and the InVu polycrystalline brackets. In tests with artificial saliva, the Radiance and the 20/40 brackets had statistically similar friction coefficients and both were greater than that presented by the InVu brackets. The artificial saliva did not change the maximum friction force of the Radiance brackets, but, for the others (20/40 and InVu), an increase of friction was observed in its presence. CONCLUSION: The InVu brackets showed, in the absence and in the presence of saliva, the lowest friction coefficient.

scholarly journals Friction Forces during Sliding of Various Brackets for Malaligned Teeth: An In Vitro Study

2013 ◽  
Vol 2013 ◽  
pp. 1-11 ◽  
Author(s):  
Vito Crincoli ◽  
Letizia Perillo ◽  
Maria Beatrice Di Bisceglie ◽  
Antonio Balsamo ◽  
Vitaliano Serpico ◽  
...  
Keyword(s):  
Friction Force ◽  
In Vitro Study ◽  
Friction Forces ◽  
Orthodontic Wire ◽  
Conventional Brackets ◽  
Frictional Forces ◽  
The Right ◽  
Post Hoc ◽  
Sliding Mechanics

Aims. To measure the friction force generated during sliding mechanics with conventional, self-ligating (Damon 3 mx, Smart Clip, and Time 3) and low-friction (Synergy) brackets using different archwire diameters and ligating systems in the presence of apical and buccal malalignments of the canine.Methods. An experimental setup reproducing the right buccal segment of the maxillary arch was designed to measure the friction force generated at the bracket/wire and wire/ligature interfaces of different brackets. A complete factorial plan was drawn up and a three-way analysis of variance (ANOVA) was carried out to investigate whether the following factors affect the values of friction force: (i) degree of malalignment, (ii) diameter of the orthodontic wire, and (iii) bracket/ligature combination. Tukey post hoc test was also conducted to evaluate any statistically significant differences between the bracket/ligature combinations analyzed.Results. ANOVA showed that all the above factors affect the friction force values. The friction force released during sliding mechanics with conventional brackets is about 5-6times higher than that released with the other investigated brackets. A quasilinear increase of the frictional forces was observed for increasing amounts of apical and buccal malalignments.Conclusion. The Synergy bracket with silicone ligature placed around the inner tie-wings appears to yield the best performance.

Comparison of friction of metallic and ceramic brackets during sliding mechanics after prophylaxis with sodium bicarbonate jet: An in vitro study

2021 ◽  
Author(s):  
Aline Rosa Galavotti Viana ◽  
Diego Patrik Alves Carneiro ◽  
Pricila Alves Carneiro ◽  
Américo Bortolazzo Correr ◽  
Silvia Amélia Scudeler Vedovello ◽  
...  
Keyword(s):  
Sodium Bicarbonate ◽  
In Vitro Study ◽  
Vitro Study ◽  
Ceramic Brackets ◽  
Sliding Mechanics

scholarly journals An in vitro comparison of the force decay generated by different commercially available elastomeric chains and NiTi closed coil springs

2007 ◽  
Vol 21 (1) ◽  
pp. 51-57 ◽  
Author(s):  
Ana Cristina Soares Santos ◽  
André Tortamano ◽  
Sandra Regina Frazatto Naccarato ◽  
Gladys Cristina Dominguez-Rodriguez ◽  
Julio Wilson Vigorito
Keyword(s):  
Artificial Saliva ◽  
Testing Machine ◽  
In Vitro Study ◽  
Original Length ◽  
Force Decay ◽  
Decay Pattern ◽  
The Mean ◽  
Initial Force ◽  
Elastomeric Chains

This in vitro study was designed to compare the forces generated by commercially available elastomeric chains and NiTi closed coil springs, and to determine their force decay pattern. Forty elastomeric chains and forty NiTi closed coil springs were divided into 4 groups according to the following manufacturers: (1) Morelli®, (2) Abzil®, (3) TP Orthodontics® and (4) American Orthodontics®. The specimens were extended to twice their original length and stored in artificial saliva at 37°C. Initial force was measured by means of an Instron universal testing machine and then at 1, 4, 7, 14, 21, and 28 days. The results revealed that the elastomeric chains delivered a mean initial force of 347 g for Morelli®, 351 g for American Orthodontics®, 402 g for Abzil®, and 404 g for TP Orthodontics®. The NiTi closed coil springs generated a mean initial force of 196 g for American Orthodontics®, 208 g for TP Orthodontics®, 216 g for Abzil®, and 223 g for Morelli®. The mean percentage of force decay observed after 28 days for the elastomeric chains was 37.4% for TP Orthodontics®, 48.1% for American Orthodontics®, 65.4% for Morelli®, and 71.6% for Abzil®. After 28 days, the NiTi closed coil springs presented a mean percentage of force decay of 22.6% for American Orthodontics®, 29.8% for Abzil®, 30.6% for Morelli®, and 45.8% for TP Orthodontics®. At the end of the study, significant differences were observed between the elastomeric chains and the NiTi closed coil springs. The results indicated that the studied NiTi closed coil springs are more adequate for dental movement than the elastomeric chains.

scholarly journals Evaluation of friction produced by self-ligating, conventional and Barbosa Versatile brackets

2016 ◽  
Vol 45 (2) ◽  
pp. 71-77 ◽  
Author(s):  
Jurandir Antonio BARBOSA ◽  
Carlos Nelson ELIAS ◽  
Roberta Tarkany BASTING
Keyword(s):  
Testing Machine ◽  
Frictional Resistance ◽  
The Self ◽  
Factorial Anova ◽  
Steel Wires ◽  
Universal Testing ◽  
Conventional Brackets ◽  
Conventional Type ◽  
Bracket Design

Abstract Introduction The Barbosa Versatile bracket design may provide lower frictional force and greater sliding. However, no in vitro studies have shown its sliding mechanisms and frictional resistance, particularly in comparison with other self-ligating or conventional brackets. Objective To compare the frictional resistance among self-ligating brackets (EasyClip/ Aditek, Damon MX/ Ormco and In Ovation R/ GAC); conventional brackets (Balance Roth/ GAC, and Roth Monobloc/ Morelli); and Barbosa Versatile bracket (Barbosa Versatile/ GAC) with different angles and arch wires. Material and method Brackets were tested with the 0.014", 0.018", 0.019"×0.025" and 0.021"×0.025" stainless steel wires, with 0, 5, 10, 15 and 20 degree angulations. Tying was performed with elastomeric ligature for conventional and Barbosa Versatile brackets, or with a built-in clip system of the self-ligating brackets. A universal testing machine was used to obtain sliding strength and friction value readouts between brackets and wires. Result Three-way factorial ANOVA 4×5×6 (brackets × angulation × wire) and Tukey tests showed statistically significant differences for all factors and all interactions (p<0.0001). Static frictional resistance showed a lower rate for Barbosa Versatile bracket and higher rates for Roth Monobloc and Balance brackets. Conclusion The lowest frictional resistance was obtained with the Barbosa Versatile bracket and self-ligating brackets in comparison with the conventional type. Increasing the diameter of the wires increased the frictional resistance. Smaller angles produced less frictional resistance.

scholarly journals Effects of Diode and Nd:YAG Laser Irradiation on Friction Forces Between Two Types of Ceramic Brackets and Rhodium-Coated Archwires

2021 ◽  
Vol 12 (1) ◽  
pp. e13-e13
Author(s):  
Hannaneh Ghadirian ◽  
Allahyar Geramy ◽  
Mohammad Ali Keshvad ◽  
Soolmaz Heidari ◽  
Nasim Chiniforush
Keyword(s):  
Laser Irradiation ◽  
Diode Laser ◽  
Nd:Yag Laser ◽  
Yttrium Aluminum Garnet ◽  
Testing Machine ◽  
Control Group ◽  
Friction Forces ◽  
X Ray ◽  
Custom Made ◽  
Ceramic Brackets

Introduction: Ceramic brackets have gained increasing popularity among dental clinicians and orthodontic patients but friction is a major concern when using them. This study sought to assess the effects of diode and Nd:YAG (neodymium-doped yttrium aluminum garnet) laser irradiation on friction forces between two types of ceramic brackets and rhodium-coated esthetic archwires. Methods: Thirty polycrystalline and 30 poly-sapphire brackets were divided into 6 groups (n=10) as follows: (I) control polycrystalline brackets (no laser irradiation), (II) polycrystalline brackets subjected to diode laser irradiation, (III) polycrystalline brackets subjected to Nd:YAG laser irradiation, (IV) control poly-sapphire brackets (no laser irradiation), (V) poly-sapphire brackets subjected to diode laser irradiation, and (VI) poly-sapphire brackets subjected to Nd:YAG laser irradiation. The bracket slots were laser-irradiated on a custom-made table. Sixty 5-cm pieces of rhodium-coated archwires were used for the friction test in a universal testing machine at a speed of 10 mm/min. Ten brackets from the six groups underwent scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDX). Results: The frictional resistance value of polycrystalline brackets was significantly higher than that of poly-sapphire brackets, irrespective of laser type (P<0.05). Irradiation of diode and Nd:YAG lasers, compared with the control group, had no significant effect on friction, irrespective of bracket type (P>0.05). Conclusion: It appears that diode and Nd:YAG laser irradiation cannot significantly decrease the friction. Future studies are warranted on different laser types with variable exposure.

scholarly journals Prophylaxis protocols and their impact on bracket friction force

2019 ◽  
Vol 89 (6) ◽  
pp. 883-888
Author(s):  
Sérgio Elias Neves Cury ◽  
Silvio Augusto Bellini-Pereira ◽  
Aron Aliaga-Del Castillo ◽  
Sérgio Schneider ◽  
Arnaldo Pinzan ◽  
...  
Keyword(s):  
Sodium Bicarbonate ◽  
Qualitative Analysis ◽  
Friction Force ◽  
Friction Forces ◽  
Debris Accumulation ◽  
Intergroup Comparison ◽  
Group 3 ◽  
Group 2 ◽  
Sliding Mechanics

ABSTRACT Objective: To evaluate the effect of two different prophylaxis protocols on the friction force in sliding mechanics during in vivo leveling and alignment. Materials and Methods: The sample comprised 48 hemi-arches divided into three groups according to the prophylactic protocol adopted. Group 1 consisted of patients undergoing prophylaxis with sodium bicarbonate, group 2 consisted of patients submitted to prophylaxis with glycine, and group 3 consisted of patients without prophylaxis, as a control. All patients received hygiene instructions and, with the exception of group 3, prophylaxis was performed monthly. After 10 months, the brackets were removed from the oral cavity and submitted to friction force tests and qualitative analysis by scanning electron microscopy. Analysis of variance followed by Tukey tests was performed for intergroup comparison regarding the friction force. Results: The experimental groups presented significantly smaller friction forces than the group without prophylaxis. Accordingly, qualitative analysis showed greater debris accumulation in the group without the prophylactic procedures. Conclusions: Prophylactic blasting with sodium bicarbonate or glycine can significantly prevent an increase of the friction force during sliding mechanics.

scholarly journals Original vs Non-Original “Cast-To” Gold Abutment-Implant Connection: Analysis of the Internal Fit and Long-Term Fatigue Performance

2020 ◽  
Author(s):  
Raquel Alonso-Pérez ◽  
José F. Bartolomé ◽  
Cristina Fraile ◽  
Guillermo Pradíes
Keyword(s):  
Artificial Saliva ◽  
Testing Machine ◽  
Cyclic Fatigue ◽  
Fatigue Performance ◽  
Tight Contact ◽  
Implant Abutment ◽  
Implant System ◽  
Internal Fit

Abstract Background: Restoring implants with not original abutment-implant connection are widely used by clinicians. Due to the current scarcity of in-vitro studies about compatible abutments and lack of relevant clinical studies, long-term fatigue performance of non-original abutments should be analyzed. The aim of this research was to assess the internal accuracy and the cyclic fatigue life after artificial aging of three implant-abutment configurations restored with one original and two compatible non-original “cast-to” gold abutments.Materials and Methods: Forty-eight original internal hexagon connection implants were connected to three different brands of abutments (n= 16 each): one original to the implant system and two non-originals. Internal accuracy and the percentage of surface with tight contact were assessed under Scanning Electron Microscope (SEM) in twelve cross-sectioned samples at three different areas (platform, internal and screw). To evaluate the fatigue mechanical behaviour under cyclic load, samples were loaded according to the ISO Norm 14801 in a universal testing machine at 2 Hz in air. Previously, samples were aged by thermocycling with 10,000 cycles at 5 °C and 55 °C in artificial saliva. Results: Original abutments presented the best accuracy and highest percentage of tight contact in the internal areas. Meanwhile, original abutments showed the lower cyclic fatigue strength degradation and the long-term success. Conclusions: Occlusal loads are transferred more homogenously through the system when original abutments are used because the better fit between the different internal components. This fact provides the highest fatigue resistance for all the restorations studied.

scholarly journals Effects of diamond-like carbon coating on frictional and mechanical properties of orthodontic brackets: An in vitro study

2021 ◽  
Vol 0 ◽  
pp. 1-7
Author(s):  
Hikmetnur Danisman ◽  
Fatih Celebi ◽  
Sengul Danisman ◽  
Ali Altug Bicakci
Keyword(s):  
Stainless Steel ◽  
Surface Properties ◽  
Friction Force ◽  
Physical Vapor Deposition ◽  
Testing Machine ◽  
Orthodontic Brackets ◽  
Diamond Like Carbon ◽  
Dlc Coating ◽  
Steel Wires ◽  
Vapor Deposition Technique

Objectives: The aim of this study is to apply a diamond-like carbon (DLC) coating on orthodontic brackets and to examine the effects of the coating on surface properties and friction. Materials and Methods: 0.022-inch upper right canine brackets, 0.018-inch stainless steel wires, and 0.019 × 0.025-inch stainless steel wires were used in the study. Half of the brackets were treated with physical vapor deposition technique and coated with DLC. Different binary groups constituted of coated and uncoated brackets and wires were subjected to friction experiments using the Instron universal testing machine (Instron, Norwood, MA, USA). The surface properties of the coatings were evaluated using Raman, Scanning Electron Microscopy, and non-contact optical profilometer. Results: The friction force values between the DLC-coated brackets and the stainless-steel wires in both dimensions were found to be statistically significantly lower than the friction force between the uncoated brackets and the wires (P < 0.001). The surface roughness value, especially around the slot groove decreased significantly in the coated brackets (P < 0.05). DLC coating layer thickness is approximately 1.0 μm (806 nanometers). Conclusion: DLC coating improves the surface properties of orthodontic brackets, and DLC coating process remarkably reduced the friction force.

scholarly journals Influence of Exposing Root Canal Dentin to Calcium Hydroxide on Its Flexural Strength

2015 ◽  
Vol 1 (3) ◽  
pp. 143
Author(s):  
Diatri Nari Ratih
Keyword(s):  
Flexural Strength ◽  
Calcium Hydroxide ◽  
Root Canal ◽  
Artificial Saliva ◽  
Testing Machine ◽  
In Vitro Study ◽  
Control Group ◽  
Sterile Saline ◽  
Root Canal Dentin

Calcium hydroxide has been used extensively in endodontic treatments, for instance as an intra-canal dressing; however, the exposure of root canal dentin to calcium hydroxide may affect its flexural strength and could have important clinical implications for endodontic treatment. The purpose of this in vitro study was to investigate the influence of calcium hydroxide on the flexural strength of root canal dentin.Seventy-two extracted single-rooted human mandibular premolars were used in this study. Each tooth was instrumented using crown-down technique and was irrigated using sterile saline. The teeth were assigned into three groups of 24 each. The prepared root canal system of each tooth was filled with calcium hydroxide mixed with sterile saline (group 1), a calcium hydroxide commercially available product (UltraCal®) (group 2) or saline solution (group 3, as control). The apices and access opening were sealed using composite resin, and the teeth were immersed in artificial saliva. After 7, 14 and 30 days of immersion, the inner root canal dentin of 8 teeth respectively from each group were sectioned to create dentin bars (1 X 1 mm, with 7 mm in length). Each dentin bar then was subjected to a three-point bending flexural test using MTS (Universal Testing Machine). Data gathered were then analyzed using two-way ANOVA, followed by Tukey’s test with the level of significance of 95%. The results showed that exposure to calcium hydroxide either using calcium hydroxide mixed with sterile saline or UltraCal® for 14 and 30 days can reduce flexural strength of root canal dentin compared to control group (p<0.05). In contrast, after 7 days exposure, there was no significantly different of flexural strength between three groups (p>0.05).   It can be concluded that calcium hydroxide reduced the flexural strength of root canal dentin. The longer the exposure to calcium hydroxide would produce a greater effect on flexural strength of root canal dentin.   

scholarly journals Can Whitening Strips interfere with the Bond Strength of Composite Resins?

2015 ◽  
Vol 16 (4) ◽  
pp. 259-263
Author(s):  
Mateus Rodrigues Tonetto ◽  
Rudys Rodolfo de Jesus Tavarez ◽  
Leily Macedo Firoozmand ◽  
Matheus Coelho Bandeca ◽  
Shilpa H Bhandi ◽  
...  
Keyword(s):  
Hydrogen Peroxide ◽  
Bond Strength ◽  
Artificial Saliva ◽  
Large Fraction ◽  
Testing Machine ◽  
Potassium Nitrate ◽  
Composite Resins ◽  
Control Group ◽  
Bond Interface

ABSTRACT Aim The aim of this study was to investigate in vitro the bond strength of composite resins on enamel previously treated with whitening strips. Materials and methods A total of 48 bovine incisors were allocated to four experimental groups (n = 12 each): G1 (WSC)— treated with 9.5% hydrogen peroxide whitening strips (3D White Whitestrips® Advanced Vivid/CREST); G2 (WSO)—treated with 10% hydrogen peroxide whitening strips (3D WhiteTM/Oral B); G3 (WG)—treated with 7.5% hydrogen peroxide gel with fluorine, calcium and potassium nitrate (White Class®/FGM); and G4 (C)—control not subjected to bleaching treatment. The specimens were subjected to bleaching over 2 weeks following the manufacturers’ instructions. Following the elaboration of the composite resin test specimens, the samples were stored in artificial saliva and subsequently subjected to the microshear test using the universal testing machine (EMIC®). The bond strength values were analyzed by one-way ANOVA and Tukey's statistical test (5%). Results Significant differences were observed among the investigated groups (p < 0.05). The G3-WG exhibited greater values compared with the control group and the groups treated with strips, G1-WSC and G2-WSO. Analysis of the bond interface revealed that a large fraction of the failures occurred at the enamel-resin interface. Conclusion The bond strength decreased following 14 days of treatment with bleaching strips, whereas the whitening gel with 7.5% hydrogen peroxide, calcium and fluorine increased the bond strength. How to cite this article Firoozmand LM, dos Reis WLM, Vieira MA, Nunes AG, de Jesus Tavarez RR, Tonetto MR, Bramante FS, Bhandi SH, de Oliveira Roma RV, Bandeca MC. Can Whitening Strips interfere with the Bond Strength of Composite Resins? J Contemp Dent Pract 2015;16(4):259-263.

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